extends Node2D

onready var cam = $MainCamera
export var dist_max = 900
export var zoom_rate = 0.001

var levelNames = ["res://Levels/Lab.tscn", "res://Levels/Square.tscn"]
var levelScenes = []
var levelCurrentNode
var levelIndex = -1

var playerScene = preload("res://Player.tscn")
var playerActionsLeft = ["p1_left", "p2_left", "p3_left"]
var playerActionsRight = ["p1_right", "p2_right", "p3_right"]

func _ready():
	for k in range(levelNames.size()):
		levelScenes.append(null)

func _process(_d):
	move_camera()

func _unhandled_input(event):
	if event.is_action("ui_accept") and event.is_pressed():
		if get_tree().has_group("living"):
			var living = get_tree().get_nodes_in_group("living")
			if !living.empty():
				return
		start()

func start():
	# Clear if required
	if (get_tree().has_group("players")):
		var players = get_tree().get_nodes_in_group("players")
		for p in players:
			p.queue_free()
	if (levelCurrentNode):
		remove_child(levelCurrentNode)
		levelCurrentNode.queue_free()

	# Select level
	levelIndex += 1

	if (levelIndex >= levelScenes.size()):
		levelIndex = 0

	if !levelScenes[levelIndex]:
		levelScenes[levelIndex] = load(levelNames[levelIndex])

	# Load level
	levelCurrentNode = levelScenes[levelIndex].instance()
	add_child(levelCurrentNode)

	# Retrieve player spawn points
	var spawners = get_tree().get_nodes_in_group("spawn")

	# Create players
	var player

	for k in 3:
		player = playerScene.instance()
		player.grid = levelCurrentNode
		player.turn_left_action = playerActionsLeft[k]
		player.turn_right_action = playerActionsRight[k]
		player.position = spawners[k].position
		add_child(player)

	# TODO Timer
	get_tree().call_group("players", "_on_game_start")

func move_camera():
	if !get_tree().has_group("players"):
		return

	var living
	if get_tree().has_group("living"):
		living = get_tree().get_nodes_in_group("living")

	if !living or living.size() == 0:
		# Show every players
		var players = get_tree().get_nodes_in_group("players")
		center_on(players)
	else:
		# Show remaining players only
		center_on(living)

func center_on(players):
	var position_accumulator = Vector2(0.0, 0.0)
	for p in players:
		position_accumulator += p.position

	cam.position = position_accumulator / players.size()

	var dist = 0
	for i in range(players.size() - 1):
		for j in range(i + 1, players.size()):
			dist = max(dist, players[i].position.distance_to(players[j].position))

	# Extend camera zoom if liners are far from each other
	var zoom = 1.0
	if dist > dist_max:
		zoom += (dist - dist_max) * zoom_rate

	cam.zoom = Vector2(zoom, zoom)